A problem with these flights is the fact that the product may stick to the surface of the flight such that as the conveyor belt on the return trip has the flights pointing downwards, any products which were stuck onto the flight may drop off, for example on the floor below the conveyor, and thereby become contaminated and must be destroyed. This is particularly true in the food industry and the amount of product, for example when poultry, shrimp, shellfish or fish is transported on these types of inclined conveyors may be up to 15-20% which is a substantial economic loss. A further problem with the prior art flights is the fact that where product is transferred from a regular conveyor onto a conveyor including flights there is an interface zone, i.e. a distance between the conventional conveyor and the conveyor including the flights such that the flights may pass this first conveyor. As a flight passes the plane of the first conveyor an opening arises such that product may fall between the two conveyors down onto the floor or the following flight.
A similar situation is present at the top of the conveyor, where the conveyed product is delivered to the next process step, for example another conveyor. It is here necessary to arrange the conveyor below the inclined conveyor at a distance allowing the flights to pass the following conveyor. For some products the drop from the inclining conveyor to the following conveyor may damage the product or create turbulence which is not desirable in a transport line, and therefore the conveyor may work at reduced speed or be unsuitable for these types of products altogether.
From DE8915286U is a conveyor known which is provided with pivotal members, which pivotal members can be activated by rails arranged under the conveyor belts surface, such that the pivotal members are can be raised from the surface of the conveyor in order to operate as flights when it is desirable to transport objects (in the actual case vegetables, fruit and the like) up inclines. Although a scraper may be activated in order to scrape debris etc. from the upper surface of the conveyor belt, no means are disclosed for cleaning all the surfaces of the conveyor belt.